1. Field of the Invention
The present invention relates generally to an electrical socket, and more particularly relates to a so-called ZIF connector, having arrangement preventing a lever from overstress while ensuring smooth interlock between the lever and a housing of the socket.
2. Background of the Invention
Zero Insertion Force (ZIF) electrical connectors have been widely used for electrically connecting two electrical interfaces such as an electrical substrate, e.g. a PCB, and an integrated circuit (IC) package, e.g. a central processing unit (CPU).
U.S. Pat. No. 6,419,514 issued to Yu on Jul. 16, 2002; and U.S. Pat. No. 5,722,848 issued to Lai on Mar. 3, 1998 disclose typical type of ZIF connectors which have been widely applied to industry. Each of the connectors generally comprises a base mountable to a PCB, a cover moveably assembles on the base and an actuator having a lever and a cam installed in the base to drive the cover to move from a first position in which a CPU can be easily seated without any inserting force, to a second position in which the CPU is drived by the cover moving to a final position in which CPU is electrically engaged with all contacts within the base. In order to ensure the electrical connection of the CPU, an interengaging arrangement is arranged between the lever and the cover for locking the cover in the second position.
As shown in FIG. 1, the connector 8 relating to the present invention comprises a base 81 mounted to a PCB. A cover 82 is moveably assembled to the base 81, and an actuator 83 is arranged between the base 81 and the cover 82. The actuator 83 comprises a cam (not shown, but disclosed in the U.S. Pat. No. 5,722,848) to move the cover 82 to slide relative to the base 81 from a first position to a second position and a lever 831. The cover 82 defines an anchor 821 which extends from one side thereof, and the lever 831 defines a recess 8311 to engageable with the anchor 821 such that the lever 831 and the cover 82 is located in the second position.
However, even such ZIF connector 8 has been widely accepted by the industry, there is still room for improving. As known to the skill in the art and end user, in order to drive the cover 82 from the first position to the second position, the lever 831 has to firstly rotate from a vertical, which can be called an opened position, to a second position in which the lever substantially lies horizontally. When the lever 831 is finally settled, the cover 82 is also locked in the second position. When the lever 831 reaches to the second, the lever 831 needs to be pried outwards firstly so as to overcome a huddle of the anchor 821, and then swings back such that the recess 8311 could engages with the anchor 821 of the cover 82. In this critical movement, the lever can be damaged or broken if care is not taken.
Recently, a so-called LGA (land grid array) socket has been introduced to provide more advanced performance of computer, such as disclosed in U.S. Pat. No. 6,877,990 issued to Liao on Jul. 3, 2003; U.S. Pat. No. 6,780,041 issued to Ma on Oct. 7, 2003; U.S. Pat. No. 7,001,197 issued to Shiral on Oct. 30, 2003; and U.S. Pat. No. 7,140,901 issued to Lin on Dec. 5, 2005. The LGA electrical connector generally comprises an insulate housing assembled with a plurality of electrical contacts, a stiffener surround the housing with a metal clip pivotally mounted to an first end of the stiffener, and an lever pivotally assembled to an opposite second end of the stiffener. Similar to the socket discussed above, the lever has to move from a first position, generally in vertical position, to second position, generally in horizontal position, for pressing the clip toward the housing and locking the clip toward the housing when the lever is located at the second position. Again, the stiffener includes an anchor interengages with the lever so as to lock the lever at the second position to ensure the electrical interconnection between the CPU and the housing.
Again, the lever has to be pried outwardly before it reaches to its final position. Not only this will create unwanted load to the operator, but will also impose potential damages to the lever as discussed above.
In view of the foregoing, such electrical connector with improvement is provided to enhance the operability of the socket.